1. Field of the Invention
The present invention relates to an electronic device cooling system and an electronic device cooling apparatus for cooling air which is blown out by a fan provided to an electronic device mounted in a cabinet.
2. Description of Related Art
There have been generally known an electronic device cooling system (for example, see U.S. Patent No. 2006/232945) and an electronic cooling apparatus (for example, see JP-A-8-316676) in which an air-water heat exchanger is disposed at an air outlet port side of a cabinet in which an electronic device is mounted and air blown by a fan provided to the electronic device mounted in the cabinet is cooled by the air-water heat exchanger and then returned to a room.
This type of electronic device cooling system is disposed in a computer room, and cools a serve and a network device disposed in the computer room. Furthermore, with respect to this type of electronic device cooling apparatus, an apparatus provided with a heater or a moisture adsorbent/discharge material for performing humidity control of the inside of a cabinet has been proposed.
An electronic device is weak to water and thus it is desired that water is not brought into a computer room. However, in the related arts, the air-water heat exchanger is disposed in the neighborhood of the electronic device, and thus when water leakage occurs from even a part of a water circulating passage through which chiller water is circulated to the air-water heat exchanger, the electronic device may be broken by this water.
It is general that the inside of a computer room is managed to be kept at a fixed humidity and a fixed temperature, and also it is necessary to prevent dew condensation because electronic devices are weak to water as described above. However, in the related arts, the electronic equipment apparatus is provided with the heater or the moisture adsorbent/discharge material for performing humidity control, and thus the number of parts is increased. In addition, the related arts use cooling water in the neighborhood of the electronic device, and thus it is necessary to take a strict counter measure to water leakage.
Furthermore, when a plurality of electronic devices as described above are mounted in a stack style and cooled in a cabinet, the temperature of air (thermal load) which is blown from these electronic devices to the air-water heat exchanger by the fans provided to the electronic devices is different in accordance with the actuation state of each of the electronic devices. Therefore, it is desired to apply weighting to cooling power in accordance with a cooling site, for example, an area having a larger thermal load is more strongly cooled while an area having a smaller thermal load is more weakly cooled, whereby the stacked electronic devices are effectively cooled.
However, according to the related arts, chiller water which is cooled to a fixed temperature is uniformly circulated over the whole area of the air-water heat exchanger at all times irrespective of the magnitude of the thermal load, and thus it has been impossible to effectively cool the stacked electronic devices. Furthermore, chiller water which is cooled to a fixed temperature is circulated to the air-water heat exchanger, and thus energy consumption is increased.